Font-awesome: Icon request: GitLab icon update

[mocha]

What can it be used for?
There is currently a GitLab icon in FontAwesome but it isn't the official outline logo. It should get updated to the official one!

Example image (optional)

Available in the press kit here:

• https://about.gitlab.com/press/press-kit/
• https://about.gitlab.com/images/press/logo/svg/gitlab-icon-1-color-black-rgb.svg

Icon request checklist

• [ ] This is a single icon or matched pair (Ex: lock / unlock)
• [ ] The title starts with "Icon request: " and is followed by the requested icon name (Ex: Icon request: magical-unicorn)
• [ ] I have searched for existing issues and to the best of my knowledge this is not a duplicate
• [ ] I have included at least one example image if it could be helpful (optional)
• [ ] The request is for a concrete object (it's harder to make an icon to represent happiness, it's easier to make a smiley face. ☺)

[mocha]

I'm the Product Manager for the GitLab Design System -- feel free to reach out if I can help further!

[tagliala]

Hi!

Thanks for being part of the Font Awesome Community and thanks for reporting this!

Let's assign @sensibleworld